Rotary piston machine usable particularly as a thermal engine

ABSTRACT

A machine with rotary pistons having an engine unit with a cylindrical chamber, the engine having two rotors coaxially mounted in the cylindrical chamber. The first rotor is continuously rotationally driven. The second rotor is intermittently rotationally driven in a same direction as the first rotor. A transmission is connected between the rotors. This transmission includes an engaging member having a non-return mechanism. The non-return mechanism includes a first element fixed to the engine unit and a second element in engagement with the second rotor. The first and second elements are cooperative with each other through an angular blocking during the explosion and intake phase of the engine unit. The hydraulic pump has a rotor coupled to the first rotor and a stator coupled to the engine unit. A hydraulic motor is coupled to the second rotor and connected to the hydraulic pump by a hydraulic circuit. At least one valve is operatively connected to the engaging member. The valve serves to partially or totally open the hydraulic circuit during one phase of the engine unit and closes the hydraulic circuit during another phase of the engine unit. The opening or closing of the hydraulic circuit will engage or disengage the second rotor with respect to the first rotor.

The present invention relates to a rotary piston machine usableparticularly as a thermal engine, of the internal combustion or dieseltype, for example.

It is specified in the present application that half a revolution meansa rotation along a 180 degree angle.

Engines are known which comprise several pairs of pistons rotationallydriven about the axis of a power intake shaft, each pair of pistonsdetermining a variable volume chamber in which the gas mixture isintroduced during the intake phase. The rotation of the power intakeshaft results from the gas expansion during the corresponding phase ofthe thermodynamic cycle. One of the two pistons is attached to the powerintake shaft, the other piston being attached to a countershaftkinematically connected to the power intake shaft by a transmission ofmovement. The power intake shaft and the countershaft are coaxiallymounted in one another and the transmission of movement induces analternating rotational movement of the countershaft with respect to thepower intake shaft, such that the volume of the chamber determined byeach pair of pistons varies alternately between a minimum and a maximum,consistently with the phases of the thermodynamic cycle used.

A plurality of solutions have been proposed for obtaining thetransmission of movement between the power intake shaft and thecountershaft. Thus, one has proposed a transmission using ellipticaltoothed wheels, which are complex to manufacture, or off-centeredtoothed wheels whose unbalance must be compensated for by balancingweights, which increases the number of moving masses. One has alsoproposed transmissions of movement comprising two planet gearscooperating by meshing with a central gear and each affixed to a crankand connecting rod system inducing an angular reciprocating motion onthe countershaft, by means of a radial arm. Balancing weights are alsonecessary with such a solution, the crank and connecting rod systemsbeing, by their constitution, unbalance effect generators. In addition,these additional weights are positioned at a distance from an axis ofrotation, which contributes to reduce the efficiency of the engine.

One also knows from the state of the art engines equipped with tworotors mounted with an interpenetration configuration, the motion of onebeing continuous, whereas the motion of the other occurs intermittently.This type of engine comprises a disengageable means for activating thesecond rotor, said means being constituted by a transmission of movementbetween the first rotor and the second rotor.

It has appeared that the solutions proposed for obtaining thetransmission of movement are not satisfactory.

The object of the present invention is to resolve the aforementionedproblems, and the invention is related to an engine of theaforementioned type including an engine unit 1 in which a cylindricalchamber 2 is provided wherein are coaxially mounted two rotors 5, 8,with an interpenetration configuration, and which form with said chamberat least one working chamber to rotate about the geometrical axis of thecylindrical chamber 2, and in which a gas mixture prevails according tothe phases of a thermodynamic cycle, one of the two rotors, rotor 5,being continuously rotationally driven, whereas the other, rotor 8, isintermittently rotationally driven in the same direction as the first,said machine further comprising:

a disengageable means for rotationally actuating the second rotor,constituted by a means for transmitting movement between the rotor 5 andthe rotor 8, coupled to the first rotor 5, on the one hand, and to therotor 8, on the other hand, said transmission means, on the kinematicchain for transmitting movement between the rotor 5 and the rotor 8,comprising an engaging member.

This machine is essentially characterized in that it is provided with annon-return mechanism comprising a first element 12 fixed to the engineunit 1 and a second element 13 in engagement with the intermittent rotor8, said elements 12, 13 cooperate with one another through an angularblocking during the explosion and intake phases, to prevent the reversemovement of the intermittently driven rotor 8, and that the means fortransmitting movement between the rotor 5 and the rotor 8 is constitutedby:

a hydraulic pump 24 coupled, through its rotor, to the rotor 5, andthrough its stator, to the engine unit;

a hydraulic motor 25 coupled to the rotor 8 and connected to thehydraulic pump by means of a loop-through or hydrostatic transmissionhydraulic circuit;

at least one valve constituting the engaging member which, during theexplosion and intake phases, partially or totally opens the hydrauliccircuit between the motor and the pump, and closes it during thecompression and exhaust phases, the total or partial opening leading toa disengagement and the closure to an engagement.

Other advantages and characteristics of the invention will becomeapparent upon reading the description of a preferred embodiment of theinvention, with reference to the annexed drawings, in which:

FIG. 1 is a transverse cross-sectional view of an engine according to afirst embodiment;

FIG. 2 is a transverse cross-sectional view of an engine according to asecond embodiment;

FIG. 3 is a partial longitudinal cross-sectional view of the engineaccording to the invention;

FIG. 4 is a transverse cross-sectional view of a non-return mechanismaccording to a first embodiment;

FIG. 5 is a longitudinal cross-sectional view along the line 5--5 ofFIG. 4;

FIG. 6 is a transverse cross-sectional view of a non-return mechanismaccording to a second embodiment;

FIG. 7 is a longitudinal cross-sectional view along the line 7--7 ofFIG. 6;

FIG. 8 shows in a transverse cross-section a hydraulic actuator capableof being associated with the non-return mechanism;

FIG. 9 is a cross-sectional half-view of the movement transmissionmeans;

FIG. 10 is a partial cross-sectional view along the line 10--10 of FIG.9;

FIG. 11 is a cross-section along the line 11--11 of FIG. 9;

FIG. 12 is a detailed cross-sectional view along the line 12--12 of FIG.3;

FIG. 13 is transverse cross-sectional view of a hydraulic motor;

FIG. 14 a partial longitudinal cross-sectional view of a hydraulicmotor;

FIG. 15 is a schematic view of an engine comprising a plurality ofengine units distributed around a central driving shaft;

FIG. 16 is a longitudinal partial cross-sectional view of the engineaccording to FIG. 15;

FIG. 17 is a cross-section along the line 17--17 of FIGS. 16;

FIG. 18 is a cross-sectional view along the line 18--18 of FIG. 16;

FIG. 19 is a partial cross-sectional view along the line 19--19 of FIG.18;

FIGS. 20-25 show the engine intake phase according to FIG. 1;

FIGS. 26-31 show the engine compression and ignition phase according toFIG. 1;

FIGS. 32-36 show the explosion phase, and the beginning of the exhaustof the engine according to FIG. 1;

FIGS. 37-42 show the engine exhaust phase according to FIG. 1;

FIGS. 43-48 show the explosion phase taking place in the first capsulingand the intake phase taking place in the second for the engine accordingto FIG. 2;

FIGS. 49-54 show the exhaust phase taking place in the first capsulingand the compression phase taking place in the second for the engineaccording to FIG. 2;

FIG. 55 is a longitudinal cross-sectional view of a non-return mechanismaccording to a third embodiment;

FIG. 56 is a cross-sectional view, on a reduced scale, along the line56--56 of FIG. 55;

FIG. 57 is a longitudinal cross-sectional view of a fourth embodiment ofa non-return mechanism;

FIG. 58 is a cross-sectional view, on a reduced scale, along the line58--58 of FIG. 57;

FIG. 59 is a cross-sectional view, on a reduced scale, along the line59--59 of FIG. 57;

FIG. 60 is a cross-sectional view of a pump and hydraulic motor assemblyaccording to another embodiment;

FIG. 61 is a cross-sectional view along the line 61--61 of FIG. 60;

FIG. 62 is a longitudinal cross-sectional view of a variation of theengine according the second embodiment;

FIG. 63 is a cross-sectional view along the line 63--63 of FIG. 62;

FIG. 64 is a cross-sectional view of a pump according to anotherembodiment;

FIG. 65 is a cross-section along the line 65--65 of FIG. 64;

FIG. 66 is a cross-section along the line 66--66 of FIG. 65;

FIG. 67 is a schematic view of a valve that is pilot operated andcalibrated for the discharging of the hydraulic circuits;

FIG. 68 is a view of a ring along the arrow F of FIG. 60.

The rotary piston machine according to invention, as shown, usableparticularly as a thermal engine of the internal combustion type, forexample, or of the diesel type, comprises at least one engine unit 1wherein a cylindrical chamber 2 is bored, in which two bearings 3,mounted at a distance from one another, are adapted to support a hollowrotor 5 constituting the engine power output shaft.

A sealing barrier constituted by a lip joint (FIG. 3), for example, isarranged at the level of each bearing 3, between the body 1 and therotor 5.

The generally cylindrical hollow rotor (5) is crossed right throughalong its longitudinal axis by a cylindrical bore 6.

The rotor 5 comprises at least one recess 7 radially to the bore 6. Thisrecess assumes the contour of a circular ring sector, along a sectionperpendicular to the axis of the rotor 5. The recess 7 has a rectangularor square cross section along a section containing the longitudinal axisof the rotor.

As can be seen in FIGS. 1, 2, 3, and 63, the recess 7 opens in the bore6 and is demarcated by said bore, through two surfaces 7A, 7B which canbe planar (FIGS. 1, 2, 3) or non-planar (FIG. 63), angularly spaced fromone another and each arranged in a geometrical plane parallel to thelongitudinal axis of the rotor. The recess is further demarcated by twolateral planar surfaces 7C each arranged according to a planeperpendicular to the longitudinal axis of the rotor 5.

By way of example merely provided as a guide, the surfaces 7A and 7B areangularly separated from one another by means an arc of a circumferencewhose value is greater than 110°. Preferably, the engine comprises atleast two diametrically opposing working chambers and, to this end, atleast two diametrically opposing recesses 7 are provided in the rotor 5,these recesses being angularly separated from one another by two solidportions 5A of the rotor 5 which have a cross section in the shape of acircular ring sector. The solid portions 5A each constitute a piston.

The rotor 5 has, on its external cylindrical surface, one or moreprojecting seal beads 4 that can be continuous, arranged about theopening of each recess 7.

These external seal beads 4 form a continuous sealing barrier around theopening of each recess 7 and are housed in grooves provided around theopenings of these recesses. These continuous seal beads are formed, forexample, by known sealing segments, joined together to form a singlepiece. These seal beads 4, as described, are subject to come intocontact with the cylindrical surface of the chamber 2.

In the rotor 5, as previously described, a second rotor 8 isrotationally mounted, constituted by a shaft 9 rotationally engaged intothe bore 6 of the first rotor and by at least one piston 10 radiallyfixed to said shaft 9 and engaged into the recess 7.

Through the shaft 9, the rotor 8 is supported by two bearings 11 eachmounted at a distance from one another in a housing coaxial to the bore6 of the rotor 5. Seal beads that can be of the type of those describedpreviously are arranged between the bore 6 of the rotor 5 and the shaft9 of the rotor 8, especially around the openings of the recesses 7, inorder to form a continuous sealing barrier at this level.

The rotor 8 preferably comprises at least two diametrically opposingpistons 10 housed in the two recesses 7, respectively. Each piston 10comprises, in its periphery, a sealing segment subject to come againstthe cylindrical surface of the chamber 2, on the one hand, and againstthe surfaces 7C of the recess 7, on the other hand, this sealing segmentpreferably assuming the contour of a "U".

The two pistons 10 are rooted in a same body extending diametricallythrough the shaft 9 of the second rotor 8 and form a single piece withthe body, as can be seen more particularly in FIGS. 1 and 2. In FIG. 63,one can see that the pistons 10 are rooted directly in the shaft 9.

Each piston 10 forms two working chambers with the cylindrical chamber 2and with the corresponding recess 7, i.e., with the lateral surfaces 7C,the surface 7A of one of the pistons 5A and the surface 7B of the otherpiston 5A.

According to the preferred embodiment of the invention, only one ofthese two working chambers is used to enable the gas mixture to prevailaccording to the thermodynamic cycle, but in a variation, one couldprovide the use of these two working chambers. In the annexed Figures,it is noted that the working chamber used is that demarcatedparticularly by the piston 10 and by the surface 7A of the correspondingpiston 5A.

During each of the four phases of the thermodynamic cycle, namely,intake, compression, ignition-explosion or combustion-explosion,exhaust, the rotor 5 constituting the power output shaft accomplishesabout a quarter revolution. During the intake phase of the gas mixturein each capsuling and the explosion phase of the gases in the latter(FIGS. 20-25, 32-36, 43-48), the rotor 8 is subject, by a non-returnmechanism to remain angularly fixed with respect to the engine unit, atleast in the reverse direction, whereas during each of the compressionphase of the gas mixture and the exhaust phase of the exhaust gases(FIGS. 26-31, 37-42, 49-54), it is subject by a movement transmissionmeans to accomplish about half a revolution with respect to the engineunit. During these two phases, the rotor 8 accomplishes about a quarterrevolution with respect to the rotor 5.

The rotor 8 can occupy two distinct and diametrically opposing stoppositions one of which coincides with that which it occupies during theexplosion phase, and the other coincides with that which it occupiesduring the intake phase. The non-return mechanism is intended to opposethe reverse movement which the rotor 8 could perform, particularly underthe effect of the torque induced by the thrust forces which are exertedon at least one of the pistons 10 during the gas expansion phase.

This non-return mechanism comprises a first element 12 mounted in ahousing coaxial with the chamber 2 and fixed to the engine unit 1, and asecond element 13 engaged with the rotor 8 and mounted in the first, oneof the two elements being a ratchet wheel comprising at least twodiametrically opposed teeth 14 that define the two stop positions of therotor 8. The other element comprises two diametrically opposed radialpins 15 each movably mounted in a bore from a set-back or retractionposition towards an exiting position along which each of them engagesinto the corresponding tooth 14 so as to ensure an angular blockage ofthe rotor 8 along a direction contrary to the direction of rotation ofthe rotor 5.

Preferably, the pins 15 form pistons in their bore and are mobilizedtowards their position for exiting and engaging their tooth 14 by aspring and/or by the hydraulic pressure delivered by a hydraulicpressure source.

In FIGS. 4 and 5, a non-return mechanism is shown which comprises anexternal ratchet wheel, the pins 15 being slidably engaged into a commonbore provided in a cylindrical body affixed to the rotor 8, said borebeing capable of being supplied with hydraulic pressure through an axialperforation connected to a conduit for supplying pressurized hydraulicfluid by means of a rotating joint.

According to another embodiment, such as shown in FIGS. 6 and 7, theratchet wheel is affixed to the rotor 8, the two pins 15 being mountedin two opposed bores aligned with one another along a same diameter.According to this embodiment, the two bores can be connected to a samepressure source. Each pin 15 of either embodiment can be associated witha resilient member such as a coil compression spring mounted in thecorresponding bore. This resilient member applies a thrust action on thecorresponding pin 15 towards its exiting position.

The first element 12 of the non-return mechanism is fixed to the engineunit by means of a system 30 for absorbing and dissipating themechanical shocks. This system is constituted, for example, by aplurality of shock absorbing elements uniformly distributed in theannular interval between the first element 12 and the engine unit, indeformable cells each demarcated by two radial walls extending in theannular interval of which one is fixed to the first element and theother is fixed to the engine unit.

The source of hydraulic pressure for activating the pistons 15 towardstheir position of engagement into the teeth 14 can be constituted by ahydraulic actuator 16 having an off-centered rotor and two movableblades 17.

The blades 17 divides the inner volume of the stator of the hydraulicactuator into one front chamber 18 and one rear chamber 19 connected toone another through a non-return valve 20.

An annular groove 21 is machined in the surface of the stator, eachblade 17 being subject to slide, through one of its ends, to slide onthe edges of such groove.

The cylindrical housing comprises two diametrically opposed sealingsegments 22 in the groove 21, the angular position of the sealingsegments 22 coinciding with the two stop positions of the rotor 8. Theblades 17 are slidably mounted in a diametral housing of the rotor ofthe hydraulic actuator. The two chambers 18 and 19 communicate with oneanother through the groove 21 when the blades 17 are angularly offsetwith respect to the sealing elements 22. On the other hand, when theblades are aligned with the sealing segments 22, the front 18 and rear19 chambers communicate with one another only by means of the non-returnvalve 20 which prevents any oil back flow from the rear chamber 19towards the front chamber 18.

A slight reverse movement of the rotor 8 drives the rotor of theactuator in the same direction, which creates an excessive pressure inthe rear chamber 19 of the actuator 16, and this excessive pressure isused to activate the radial pins 15 in the direction of engagement inthe teeth 14 of the ratchet wheel. To this end, the rear chamber 19 ofthe actuator 16 is in communication with the bore(s) of the radial pins15. According to the preferred embodiment of the invention, to ensurethis communication, each blade 17, from its end that is the closest tothe center of the rotor, is provided with a groove 23 extending radiallywith respect to the off-centered rotor of the actuator 16, this radialgroove creating a passage towards the diametral housing of theoff-centered rotor only when the blade occupies an exiting position withrespect to this housing. This blade 17 occupies this position when itsgroove 23 is in communication with the rear chamber 19. As can be seenin FIG. 8, the groove is not provided along the entire length of theblade and its farthest end from the center of the rotor remainsdistanced from the corresponding end of the blade, such that when thelatter is totally set back in the diametral housing, the farthest endfrom the center of the rotor blocks the corresponding end of saidhousing.

The diametral housing of the off-centered rotor is in communication withthe bore(s) for guiding the pins 15 by means of a perforation and/or arotating joint.

A non-return mechanism has been previously described, whose elements 12and 13 cooperate with one another in an angular blocking by penetrationof the pins 15 in the teeth 14. According to two alternativeembodiments, as shown in FIGS. 55, 56, and 57-59, respectively, thefirst element 12 affixed to the engine unit and the second element 13affixed to the intermittently operating rotor 8 form at least one cell55 in which, during the explosion and intake phases, a volume of oil isconfined to prevent at least the reverse rotation of the second element13.

As can be seen in FIGS. 55-59, the first element 12 comprises a chamber56 in which the second element 13 is mounted. This chamber accepts thegeometrical axis of rotation of the rotors 5 and 8 as an axis ofsymmetry. This chamber is demarcated by two front 57 and rear 58 wallsspaced apart and each extending perpendicularly to the axis of symmetry,and by a casing wall 59 arranged between the front and rear walls. Thesecond element 13 of the non-return mechanism is constituted by acentral core 13A coupled to the rotor 8 and by two blades 60 extendingradially from this core, in a diametrically opposite manner.

The core 13A of the second element is prolonged axially by a channeledshaft adapted to be coupled outside the chamber 56 to a channeled sleeveprovided at the end of the rotor 8. The channeled shaft crosses thefront wall 57 right through by engaging in a bore provided in thelatter. At the level of the bore, the shaft is smooth so as to cooperatewith a sealed guide bearing mounted in the bore. Opposite the channeledshaft, the central core 13A of the second element is prolonged axiallyby a second shaft engaged in a second guide bearing mounted in a boreprovided in the rear wall 58. The surface 59A inside the chamber 56 ofthe casing wall 59 comprises two diametrically opposed surface sectors61 with respect to the axis of rotation of the second element 13 againstwhich the ends of the radial blades 60 are pressed when the two elementsof the non-return mechanism are in a relation of angular blockage withrespect to one another. One of the two elements of the non-returnmechanism carries, in the chamber, two sealing members 62 eachpreferably constituted by a flap and the other element of the non-returnmechanism is provided, in the chamber, with two diametrically opposedsurface sectors 63 with respect to the axis of rotation of the secondelement against which the sealing members 62 are pressed when the twoelements 12 and 13 are in a relation of angular blockage with respect toone another. As can be seen in FIGS. 56 and 58, the surface sectors 63are closer to the axis of rotation of the second element than thesurface sectors 61. In the position of angular blocking of the twoelements 12, 13, one with respect to the another, the blades 60, thesealing members 62 and the surfaces inside the chamber of the front 57and rear 58 walls and casing wall 59 form two diametrically apposedimpervious cells 55 filled with oil and separated angularly from oneanother by two ullages 55A also filled with oil.

Considering the reverse direction of the engine, the sealing member ofeach cell is located in front of the blade of this cell.

The volume of oil confined in each cell opposes the variation of thevolume of the latter towards a decrease, which corresponds to thereverse direction of the movement of the second element. In this way,the second element and therefore the rotor 8 are rotationally blocked inthe reverse direction.

It must be noted that the explosion phase begins before the completestop of the intermittently driven rotor, such that at the very beginningof this phase, the rotor, in view of its inertia, performs a fraction ofrevolution while decelerating down to zero speed, then, under the effectof the pressure prevailing in the engine working chamber(s), is drivenin the reverse direction. The second element 13 of the non-returnmechanism is therefore driven by the rotor 8, first in the direction ofrotation of the engine, then in the reverse up to the blocking position.It must also be noted that the cells 55 are formed at the end of thecompression phase such that during the movement in the direction ofrotation of the engine of the second element 13, at the end of thecompression phase, and at the very beginning of the explosion phase, avacuum is created in each cell with respect to the pressure prevailingin the ullages 55A, due to the increase in the volume of the latter. Toprevent this disadvantage, a non-return valve 55D is associated witheach cell which enables the oil to be introduced into said cell, thisoil being in the ullage 55A.

Advantageously, a means is provided for indexing the position of angularblockage of the two elements 12, 13 with respect to one another, andtherefore of the rotor 8 with respect to the engine unit, this indexingmeans allowing for the reverse movement of the second element 13 towardsits blocking position by controlling this movement.

Preferably, the two surface sectors 61 are each provided with a leakagecross-section 64, which makes it possible to obtain the indexing of theposition of angular blockage of the two elements 12, 13 with respect toone another. As long as the corresponding blade 60 is at its level, thisleakage cross-section 64 allows for a slight reverse movement of thesecond element 13 which will be blocked angularly as soon as the bladewill have passed through the leakage cross-section 64.

In a strict sense, the angular stop position is slightly variable and isdependent upon a number of parameters among which one can cite theinternal oil leakages at the level of the cells which themselves dependupon the engine speed and the load. This stop position fluctuates aroundan original position as a function of the above-mentioned parameters.

In the embodiment shown in FIGS. 55 and 56, the blades 60 are eachslidably mounted in a groove 13B provided radially in the core 13A ofthe second element 13, and are pressed against the internal surface 59Aof the casing wall 59 by at least one resilient member 60B. In theembodiment shown in FIGS. 55 and 56, the two grooves 13B of the core 13Aare diametrically opposed, and the core 13A, from the bottom of one ofthe two grooves to the bottom of the other is crossed right through by acylindrical bore 13C in which a cylindrical finger 60A which the blade60 comprises is engaged with a sliding fit. The resilient member 60B iscompressed in the radial bore 13C between the finger 60A of one of theblades and the finger 60A of the other, this resilient member beingconstituted by a coil spring.

Advantageously, these two fingers 60A are each provided with a blindaxial perforation in which the return resilient member 60B engages.

Preferably, a plurality of bores 13C are provided, and each blade isprovided with a plurality of fingers 60A. A plurality of resilientmembers 602 are also provided, each of which comes to be positioned in abore, in compression between the finger of one of the blades and thefinger of the other.

The core 13A of the second element carries the two sealing members 62which occupy a stationary position with respect to the latter, and areangularly distanced from the blades 60. According to this embodiment,the surface sectors 63 are formed in the surface 59A of the casing wall59, with an angular spacing from the surface sectors 61, and saidchamber assumes a substantially oval contour. Each sealing member 62,according to this embodiment, forms a projection on the core and ismaintained in a stationary angular position with respect to the latteragainst a stop surface for the core by a resilient member such as a leafspring.

It must be noted that the surface sectors 61 and 63 can be part ofcylindrical surfaces.

A plurality of channels 55B provided in the front wall 57 lead to ineach cell 55 formed during the angular blocking of the two elements 12,13, with respect to one another. Each of these channels further leads tothe end of a blind bore provided in this wall. A cylindrical buffer 55Cfor support against the engine unit is slidably mounted in the blindbore. The front wall 57 is mounted with a possibility of limited axialdisplacement. When the two elements 12, 13 are in a blockingrelationship, the oil confined in each cell 55 is pressurized and isintroduced under pressure through the channel 55B into the gap betweenthe end of the bore and the support buffer 55C. The latter is thenpressed against the engine unit and, by reaction, the wall 57 is appliedagainst the core 13A thus limiting the operational backlash and,therefore, the internal oil leakages at the level of the lateral side ofthe blades 60 and of the sealing members 62. As the coupling of thesecond element 13 to the rotor 8 allows it the possibility of displacingaxially, the action that it withstands from the front wall 57 forces itscore 13A to press against the rear wall 58. In this manner, during theangular blocking, the functional backlashes are eliminated, the oilleakages limited and the sealing ensured.

In the embodiment shown in FIGS. 57-59, the blades of the second element13 are fixed with respect to the core 13A of the latter, and the surfacesectors 61 and 63 belong respectively to cylindrical surfaces. Thesectors 63 are arranged on the core 13A with angular spacing of theblades 60. The cylindrical surface carrying the cylindrical sectors 61has a greater diameter than the cylindrical surface carrying the sectors63.

Furthermore, according to this embodiment, the sealing members 62 arefixed in a journalled manner to the first element 12 and are driven intheir pivoting movement towards the core 13A of the first element 13 oraway therefrom by at least one cam 65 coupled to the continuously drivenrotor 5, or as a variation, to the intermittently driven rotor. As canbe seen in FIG. 58, the cylindrical surface sectors 61 are both formedin two excessive thicknesses, respectively, of the cylindrical envelope,these two excessive thicknesses being diametrically opposed.

Each flap 62 comprises a base 66 provided with retention pins 67 engagedin two perforations provided opposite one another in the front wall 57and in the rear wall 58, along the pivoting axis of the flap. An arm 68in the form of a torsion spring is fixed to the base 66, at the end ofwhich arm is mounted a finger 69 coming into a sliding support on thecam surface 65 which is preferably provided in a sleeve coupled to therotor 5 and arranged at the front of the front wall 57.

As can be seen in FIGS. 57 and 59, two cams 65 arranged side by side areprovided, and two fingers 69 cooperating respectively in a slidingsupport with the two cam surfaces are mounted at the end of the tensionspring of each flap. These two cams 65 alternatively drive and controlthe rocking movement of the associated flap 62.

As an alternative, one can provide a came surface coupled to theintermittent driven rotor. Therefore, this cam surface can be providedon the second element 13 of the non-return mechanism, and the flap 62will cooperate in a sliding support with the cam surface. It can bemaintained in support against this surface by a return elastic elementthat can be constituted by a torsion spring fixed to its base, on theone hand, and to one of the front 57 and rear 58 walls of the chamber56, on the other hand.

The base of the flap 62 has a guiding convex surface in the form of acylindrical surface sector whose axis is that of pivoting of the flap.This cylindrical surface sector is subject to slide during the pivotingof the flap against a concave surface in a cylindrical sector providedin the surface 59A of the casing wall 59, laterally to one of theexcessive thicknesses. A ribbed bulging is rooted in the base 66 of theflap, which bulging carries, at a distance from the base 66, a flap head62A which, in the blocking position of the two elements 12, 13 withrespect of one another, is positioned in contact with one of thecylindrical surface sectors 63 of the second element 13 and extendsbetween this second element 13 and the surface 59A of the casing wall59.

As can be seen in FIG. 58, the head 62A of the flap 52 has a headsurface in the form of a cylindrical surface sector whose axis ofrevolution is merged with the pivoting axis of the flap 62. The flap 62,in its pivoting movement, is guided by the convex surface of its basebrought to slide against the concave surface of the casing wall lateralto one of the excessive thicknesses, on the one hand, and by the headsurface brought to slide on a sealing segment mounted in a grooveprovided in the other excessive thickness, on the other hand.

Preferably, each flap 62 is crossed right through by a channel, from thehead surface to the base. As can be seen in FIG. 58, when the head andthe blade form the cell 55, this channel is in relation with said cell,such that the pressurized oil arrives between the base of the flap andthe surface 59A of the casing wall 59. This arrangement ensures thehydrostatic equilibrium of the flap 62.

During the compression phase and the exhaust phase, the second element13 is rotationally driven, and each flap 62 is distanced from the core13A of the second element 13 and from the path of the blades 60 by meansof a cooperation of the cams 65, the fingers 69, and of the arm 68. Toensure the angular blocking of the second element 13 during the intakeand explosion phases, the flaps 62 are brought back against the core ofthe second element 13. To balance the pressures in the cells 55, thelatter can be connected to one another by a balancing channel providedin the core 13A.

Finally, it must be noted that the non-return mechanism according to thelast two embodiments is provided with an oil inlet opening in at leastone of the two ullages 55A, and with an oil outlet to ensure the changeand the cooling of the oil.

The means for activating the rotor 8 rotationally activates the latterduring the compression and exhaust phases. It is preferably coupled tothe rotor 5 and to the rotor 8, and ensures the transmission of therotational movement. An engaging member which occupies a disengagedposition during the intake and explosion phases is preferably arrangedon the kinematic chain for transmitting the movement between the firstrotor 5 and the second rotor 8, such that the rotational movement of therotor 5 is no longer transmitted to the rotor 8 during these phases.During the compression and exhaust phases, the engaging member occupiesan engaged position, such that the rotor 8 is activated in rotation.

This activation means is constituted by a hydraulic pump 24 coupled bymeans of its rotor to the rotor 5 and by means of its stator to theengine unit, as well as by a hydraulic motor 25 coupled to the rotor 8and connected to the hydraulic pump by means of a hydraulic circuit.Preferably, the hydraulic motor is coupled to the rotor 5 by means ofits stator, whereas it is coupled to the rotor 8 by means of its rotor.Thus, the stator of the hydraulic engine is rotationally driven by therotor 5. The quantity of oil provided to the hydraulic motor 25 by thepump 24 causes a relative rotation of the second rotor 5 with respect tothe first rotor 8.

It must be noted that in order to consider the compressibility and theleakages of the oil, which are dependent upon the engine speed and theload, the hydraulic pump provides the hydraulic motor with a quantity ofoil slightly greater than theoretically necessary. This difference wouldcumulate upon each revolution of the rotor and in the absence of anindexation at the level of the non-return mechanism. This would lead toprogressively offset the relative position of the intermittentlyoperating rotor 8 with respect to the continuously operating rotor 5, upto an equilibrium position where the pressures involved lead tocompressions and leakages of oil such that this difference iseliminated. Thus the compression ratio would tend to diminish when thetorque increases and the speed decreases. These effects aresubstantially attenuated due to the indexing of the angular blockingposition.

The activation means preferably comprises an engaging memberconstituted, for example, by a valve which, during the intake andexplosion phases, partially or totally opens the hydraulic circuitbetween the motor and the pump, and closes it during the compression andexhaust phases.

Preferably, the hydraulic motor 25 comprises at least one rear chamberand at least one front chamber both connected to the hydraulic pump 24by means of the hydraulic circuit. The engagement member constituted bya rotating valve, for example, is arranged on this hydraulic circuit.This rotating valve creates a hydraulic shunt, during the intake andexplosion phases, by connecting the front and rear chambers of thehydraulic motor to one another, as well as the inlet and outlet of thehydraulic pump, which then discharge themselves, this hydraulic shuntbeing comparable to the opening of the hydraulic circuit between thepump and the engine.

The hydraulic pump 24 comprises radial pistons 26 each slidably mountedin a cylindrical chamber 27 provided radially in its rotor. The pistonseach comprise at least one roller 28 subject to roll successively duringthe rotation of the rotor on internal came surfaces 31 provided in thestator of the pump.

According to the preferred embodiment of the invention, the pump 24 isequipped with four systems of piston 26 and cylindrical chamber 27,these systems being opposed two by two along a same diameter and beinguniformly spaced from one another, the angular spacing between twoconsecutive systems being 90°. Each system, through its chamber 27, ishydraulically connected to the chamber 27 of the opposite system bymeans of at least one diametral perforation, in order to balance thepressures. Therefore, two diametrically opposed systems operate togetherand are both connected to one of the chambers 25 of the hydraulic motorby one or more conduits 29A. The other chamber of this hydraulic motoris connected to the other two systems by one or more hydraulic conduits29B. These systems are functionally arranged by groups, one of the twogroups being hydraulically connected to the rear chamber of the engine,and the other to the front chamber.

The stator of the pump 24 is equipped with four cam surfaces 31positioned behind one another around the rotor. At every moment, eachcam surface 31 cooperates with only one piston 26. These came surfacesare configured so as to enable, during the rotation of the rotor of thepump, the movement towards the center of the rotor of the two pistons ofone of the groups of the systems, and the movement of the other twopistons of the other group towards the periphery of the rotor. As aresult, there is a volume variation in the chambers 27 of the systems atevery moment, the absolute values of the instantaneous volume variationsbeing substantially equal.

Preferably, the hydraulic motor is structured based on the samearchitecture as that of the thermal engine described previously. Thus,the hydraulic motor 25 (FIGS. 13, 14 and 60) is constituted by at leasttwo consecutive working chambers obtained by rotors 5' and 8', one ofthese working chambers constitute the front chamber and the other therear chamber. The rotors 5' and 8' constituting the stator and therotor, respectively, of the hydraulic motor, can be independent elementscoupled to the rotors 5 and 8, respectively, or can be constituted by aportion of the rotors 5 and 8, respectively. The rotors 5' and 8' aremounted with an interpenetration configuration, and the rotor 5' ishollowed and comprises two recesses 7' having the same shape as therecesses 7 of the rotor 8, and two pistons 5'A having the same shape asthe pistons SA of the rotor 5, said pistons 5'A having a face 7'A and aface 7'B.

The two diametrically opposed pistons 10' of the rotor 8' are displacedin the diametrically opposed recesses 7'. The rotors 5' and 8' aremounted in a cylindrical chamber 2' formed in a tubular element 54, therotors 5', 8' and the cylindrical chamber are coaxial. The tubularelement 54 is fixed to the rotor 5', the latter is force fitted in thecylindrical chamber 2' through the cylindrical surface of each of itspistons 5'A. The pistons 5'A, 10' and the cylindrical chamber form fourworking chambers that are diametrically opposed two by two.Advantageously, four working chambers are used, the internal volumes oftwo diametrically opposed working chambers will constitute the rearchamber of the hydraulic motor, the internal volumes of the other twowill constitute the front chamber. The front chamber of the motor isdemarcated between the faces 7'B and the pistons 10', the rear chamberbetween the faces 7'A and the pistons 10'. Two conduits open on bothsides of each piston 5'A, one of which is supply conduit 29A and theother is the delivery conduit 29B.

The tubular element 54 can be mounted in rotating guide bearings and canbe fixed to the rotor of the pump 24. It can also be integral with therotor of the pump 24.

The hydraulic motor will be axially spaced from the thermal engine andformed in the cold portion of the engine unit.

The hydraulic motor and the thermal engine operate in phase.

During the compression and exhaust phases, the front chamber of thehydraulic motor is fed with hydraulic fluid by the hydraulic pump 24,whereas the fluid in the rear chamber of this motor is led to flow backtowards the pump, which enables the rotor 8 to be driven alongapproximately a quarter revolution with respect to the rotor 5, thelatter accomplishing about a quarter revolution during these phases, theassociation of these two relative motions leading the rotor 8 toaccomplish about half a revolution with respect to the engine unit.

By way of example, during each of the compression and exhaust phases,the rotor 5 can accomplish a 100-degree rotation with respect to theengine unit, while the rotor 8 makes a 80-degree rotation with respectto the rotor 5.

The movement of the rotor 8 is first accelerated to a maximum speed, andis then decelerated. The feeding of the front chamber of the hydraulicmotor ensures the mobilization of this rotor 8 during the accelerationphase of the rotation movement. This mobilization is controlled duringthe deceleration phase of the rotor 8 by the rear chamber of thehydraulic motor. The flow of oil supplied by the pump to the frontchamber of the hydraulic motor during the compression phase is thereforevariable, i.e., it first increases, and then decreases. The accelerationof the movement of the rotor 8 corresponds to the increasing phase ofthe flow rate, while the deceleration of the movement of the piston 8corresponds to the decreasing phase, this movement being stillcontrolled by the rear chamber of the hydraulic motor. During thecompression phase, the oil in the rear chamber of the hydraulic motor isled to flow back towards the pump, still with a variable flow rate.

Thus, the connection between the hydraulic motor 24 and the hydraulicpump 25 is a hydrostatic transmission when the actuation means isengaged and the motor and the pump therefore operate in a closed loop.

The rotational speed of the intermittently driven rotor is constantlycontrolled by the hydraulic pump, whether in the acceleration period, orin the deceleration period. The law of motion of the hydraulic motor isdirectly related to the flow rate of the oil admitted in the hydraulicmotor. Except for the oil leakages and compressibility, the law ofmotion of the motor 25 is directly based on the law of flow rate of thepump 24 imposed by the geometry of the cam surfaces 31.

During the compression and exhaust phases, the front and rear chambersof the hydraulic motor are isolated from one another by the rotatingvalve, which enables the mobilization of the rotor 8. On the other hand,during the explosion and intake phases during which the movement of therotor 8 must be interrupted, the rotating valve ensures thecommunication between the front and rear chambers of the hydraulic motor25 and the inlet and outlet of the pump 24.

The rotating valve establishes a hydraulic communication between theconduits 29A and 29B, which creates a hydraulic shunt. Thiscommunication is interrupted during the compression and exhaust phases.

A conduit 29A or 29B is associated with each cylindrical chamber 27,depending upon whether this chamber 27 is connected to the internalvolume of one of the working chambers forming the front chamber of themotor 25 or to the internal volume of one of the working chambersforming the rear chamber of this motor. Therefore, two conduits 29A andtwo conduits 29B are formed. Each conduit 29A or 29B is positioned, onthe one hand, between the associated chamber 27 and the correspondingworking chamber and, on the other hand, between said chamber 27 and therotating valve. These conduits 29A, 29B are provided in the rotor of thepump. The two conduits 29A are diametrically opposed. The conduits 29Bare arranged in a similar manner.

This rotating valve is, for example, constituted by a disk 32 whichconstitutes the bottom of a cylindrical chamber 32A fixed to the engineunit, coaxially thereto, in which four tubular cylindrical end pieces 33penetrate so as to extend the four conduits 29A, 29B, respectively, inthe volume of the chamber. The end pieces are mounted with a closesliding fit in their respective conduit, and a resilient member isassociated with each of them to maintain it in contact with the disk.The end pieces 33 of the conduits 29A are diametrically opposed, so arethe end pieces for the conduits 29B. The end pieces of the conduits 29 Acan be angularly offset by 90° with respect to those of the conduits29B. With respect to the disk, the two end pieces 33 associated with theconduits 29A move about a common circular orbit that is different fromthe common orbit about which the end pieces of the conduits 29B move. Oneach of the circular orbits of the end pieces 33 of the conduits 29A,29B, the disk has two diametrically opposed grooves 34 which extendalong an arc of circumference substantially equal to 90°. The groovesprovided about one of the two orbits are offset by 90° with respect tothe grooves 34 provided about the other orbit.

The disk of the rotating valve is wedged angularly with respect to themotor such that the beginning of the intake and explosion phasescoincides with the positioning of the end pieces 33 on the upstream endof the grooves 34. The external diameter of each end piece 33 is greaterthan the width of each groove, such that the end piece 33, when oppositethe groove, slides on the edges of the latter. Each end piece 33 isopposite one of the grooves on its orbit during the explosion and intakephases, as a result, the conduits 29A and 29B are in communication withone another by means of the volume of the cylindrical chamber 32A andthe grooves 34. During the compression and exhaust phases, the endpieces 33 are spaced angularly from their respective groove 34 and areblocked by the planar surface of the disk 32, which interrupts thecommunication between the conduits 29A and 29B.

It is obvious that this hydraulic valve is only provided by way ofexample, and that any other hydraulic member adapted to the function canbe used, in particular those shown in FIGS. 17, 18, 61, 61b is, 64, 65and described hereinafter.

We have previously described a hydraulic motor and a hydraulic pumpaxially offset as can be seen in FIG. 9, but in a variation, as shown inFIGS. 60 and 61, the motor is housed in the pump and is formed in therotor of the latter. Thus, the conduits 29A and 29B extend radially fromthe corresponding capsulings of the hydraulic motor towards thecorresponding chambers 27 of the pump.

As can be seen in this Figures, the stator of the pump forms animpervious housing in which the rotor of the pump moves rotationally. Inaddition, the impervious housing is filled with oil. In FIGS. 60 and 61,it is noted that the pistons do no longer comprise any roller 28, buteach comprises a sliding pad 70 adapted to slide on the concave camsurfaces 31 that are preferably provided in an internal crown 24A of thestator of the pump 24. This crown, as can be seen in FIG. 61, comprisestwo lateral surfaces 24B perpendicular to the axis of rotation of therotor.

Each sliding pad 70 has a spherical cap-shaped convex surface 71 whichcomes into support in a substantially conical flaring 72 provided in thepiston 26. This arrangement allows the pivoting of the pad with respectto the piston.

The sliding pad 70 is provided with two parallel flanks 73 positioned onboth sides of the crown 24A, in sliding contact with the two lateralsurfaces 24B of the latter.

The sliding pad 70 further comprises two parallel support lips 74,spaced from one another, each extending continuously from one flank 73to the other. These two lips, normal on the flanks 73, providetherebetween either a depression or a planar portion in which opens achannel 75 crossing the sliding pad 70 right through to open in thespherical cap-shaped surface of the latter. The piston 26, along itsaxis, is also crossed right through by an axial channel 76 that opens inthe chamber 27, on the one hand, and in the flaring 72, on the otherhand. Due to this arrangement, pressurized oil can be inserted betweenthe piston and the pad, on the one hand, and between the pad 70 and thecam surface 31, between the two lips 74, on the other hand. Thisarrangement reduces the intensity of the resultant of the forcesgenerated by the oil pressure exerted on the assembly constituted by thepad 26 and the piston 70, on the one hand, and on each of the twoelements 26 and 70, on the other hand, and creates a hydrostatic balanceof these elements.

The rotor of the pump is equipped with two disk-shaped flanks 77 whichcome to be positioned on both sides of the internal crown 24A. At thelevel of each piston 26/sliding pad 70 assembly, the flanks 77 of therotor of the pump are each equipped with a radial opening 78 between theedges of which the sliding pad 70 is mounted through one of its flanks73. The rear edge of each opening 78, considering the direction ofrotation of the rotor of the pump, comes into contact with thecorresponding flank 73 of the pad. To be capable of pivoting freelywhile remaining in contact with the corresponding rear edge, each flank73 of the sliding pad 70 assumes the contour of an arc of circumferenceof a circle.

Thus, the sliding pad is guided, on the one hand, by the lateral flanks24B of the crown 24A and, on the other hand, by the edges of the radialopenings 78 of the flanks 77.

The rotating valve of the pump according to this embodiment isconstituted by the circular crown 24A, on the one hand, and by thesliding pad, on the other hands. Two diametrically opposed grooves aredug in the circular crown 24A, from each of the lateral surfaces 24B,each of these grooves contiguous to a cam surface 31 and extendingparallel to the corresponding cam surface. The two grooves 24C dug inthe crown, from one of its lateral surfaces 24B, are offset by 90° withrespect to the grooves 24C dug in the crown 24A from the other lateralsurface. The grooves are arranged on the orbits of the flanks 73 of thesliding pad 70. The two grooves of one of the lateral surfaces 24B areadapted to cooperate with the systems of chambers 27 and pistons 26assigned to controlling the mobilization of the rotor 8' of thehydraulic motor. The other two grooves are adapted to cooperate with theother two systems, the latter being in relation with the rear chambersof the hydraulic motor and being assigned to the mobilization of therotor 8' during the decelerating phase thereof.

The grooves adapted to cooperate with the systems assigned to themobilization of the rotor 8' are respectively contiguous to the two camsurfaces cooperating, during compression and exhaust, with the twosystems assigned to the control of the deceleration, whereas the twogrooves adapted to cooperate respectively with the two systems assignedto the control of the deceleration are respectively contiguous to thetwo cam surfaces cooperating with the other two systems during thecompression and exhaust phases. On the side of their respective grooves,the systems in the corresponding flank 73 of their sliding pad 70 areeach provided with a cut 73A that ensures the communication between thegroove and the interval between the support lips 74. The functioning ofthis rotating valve is consistent with that described previously.

The cam surfaces 31 of the rotary piston pump according to the twoembodiments preferably ensure a sinusoidal variation in the volume ofthe working chamber formed by each piston 26/chamber 27 assembly. Duringthe intake and explosion phases, the instantaneous volume variation inthe front and rear chambers of the hydraulic motor is constant, whereasthe instantaneous volume variation in the aforementioned workingchambers is sinusoidal.

Thus, the flow balance in the assemblies constituted respectively by thesystems and the associated front or rear chambers of the hydraulicmotor, is first negative during the intake and explosion phase(discharge of oil), then is positive with respect to the assembliescomprising the front chambers of the hydraulic motor, and is negativewith respect to the other assemblies. This is not a hindrance sinceduring the aforementioned phases, the various assemblies are incommunication, by means of the grooves, with the internal volume of theimpervious housing formed by the stator of the pump. Thus, the excess ofoil in the assembly considered will be poured in the impervious housing,while the oil shortage will be compensated from the impervious housingof the stator under the action of the vacuum prevailing in saidassembly.

To facilitate the oil intake in the various assemblies and to avoid atoo substantial vacuum in each of them, a channel provided in the rotorof the pump, from one of the external surfaces thereof towards thecorresponding cylinder 27, for example, is provided for each of them. Anon-return valve is associated with this channel to prevent any backflow of the oil through the channel from the cylinder 27 towards theimpervious housing.

A discharge of oil for the two other assemblies corresponds to theintake of oil in the two assemblies comprising the front chambers of thehydraulic motor. This discharge of oil, which occurs from theseassemblies towards the impervious housing, is utilized to create acounterpressure in the rear chamber(s) of the motor and to prevent,especially during the gas intake phase, the rotation of the rotor 8',and thereby the rotation of the rotor 8 which may occur due to a vacuumprevailing in the motor capsuling during intake, when the thermal engineis idle or decelerated. This counterpressure can be created, forexample, by a pressure relief valve arranged on the circuit fordischarging the oil towards the impervious housing.

Preferably, the beginning of the compression phase for the thermalengine, and therefore the beginning of the pressurization of the frontchambers of the hydraulic motor correspond to the evenness of theabsolute value of the oil flow rate exiting the systems assigned to themobilization of the rotor 8' with the absolute value of the flow rate ofthe oil that can be introduced in the front chamber of the hydraulicmotor. In this way, the rotor 8' can be started without jerks.

For each working chamber, the four phases of the thermodynamic cycle areaccomplished in one complete revolution, each phase corresponding toabout a quarter revolution of the rotor 5', the rotor making a stopduring the intake phase, a half-turn rotation during the compressionphase, a stop during the ignition-explosion or combustion-explosionphase, and a half-turn during the exhaust phase.

According to a first embodiment, as can be seen in FIGS. 1 and 20-42,the same phases of the thermodynamic cycle are accomplished in the twoworking chambers.

Thus, two diametrically opposed spark plugs 35, two diametricallyopposed intake valves 36 and a plurality of diametrically opposedexhaust valves 37 grouped, for example, by pair, are used. The angularposition of one of the two pairs of diametrically opposed exhaust valvesdetermines the end of the explosion phase (see FIG. 36), the angularposition of the other pair of diametrically opposed valves correspondingto a position that is offset rearwardly by a few degrees with respect tothe angular position of the pistons 10 at the end of the exhaust phase(FIG. 42).

In order to balance the pressures, the two working chambers are incommunication with one another through an opening 51 provided in therotor 8, and more specifically in the body of the pistons 10.

Still according to this embodiment, a single pair of working chamberscan be provided, or several pairs according to another variation.According to this variation, the pairs of working chambers will beoffset axially and separated from one another by impervious partitions,the gas expansion phase in the working chambers of one of the pairs ofworking chambers being capable of corresponding to the gas intake phasein the two working chambers of the other. According to this embodiment,the separation partitions are radial partitions of the rotor 5, thelatter comprising a plurality of pairs of recesses 7 axially spacedapart with or without angular displacement of one with respect to theothers, and separated by said radial partitions. The rotor 8 accordingto this embodiment will be equipped with several pairs of pistons 10cooperating respectively with the pairs of recesses 7.

According to another embodiment (FIGS. 2, 43-54, and 62, 63), only onespark plug, one intake valve 36 or 79 and one or more exhaust openingsare provided. With such a motor, the thermodynamic cycle occurring inone of the two capsulings is offset in phase with respect to the cycleoccurring in the other, the four phases of the cycle obtained by the twoworking chambers being accomplished in half a revolution.

Advantageously, the various valves 36, 37 are controlled in thedirection of opening and closing by hydraulic members such as rotatingjacks. Each valve can be constituted by an axle mounted rotationally ina cylindrical housing provided in the thickness of the engine unit 1 andtransversely to a radial passage 38 provided in the thickness of thewall of the engine unit, this radial passage 38 being either an intakepassage or an exhaust passage. The valve will comprise a diametralperforation 39 in the form of a slot that can be aligned with the radialpassage 38 or offset angularly with respect to latter in order to createa blocking. The axle constituting the valve comprises, at a distancefrom the diametral perforation, a piston 40 arranged in a housing 41 ofthe body 1. This piston 40 divides this housing into two chambers, onefront chamber and one rear chamber. A perforation connected to ahydraulic circuit for controlling the position of the valve in relationwith the phases of the thermodynamic cycle leads to each chamber.

Each valve can also be constituted by a rotary slide valve 79, as can beseen in particular in FIGS. 62 and 63. This rotary slide valve 79 willbe housed in a cylindrical chamber of the engine unit contiguous to thecylindrical chamber 2 and in relation with the latter throughcommunication opening 80 that are alternatively blocked and cleared bythe rotary slide valve 79, consistently with the phases of thethermodynamic cycle taking place in the motor working chambers. A motoraccording to the second embodiment is shown in FIGS. 62 and 63, and therotary slide valve is associated with intake openings. In FIG. 63, onecan see that the rotary slide valve is diametrically opposed to thespark plug, and it is noted that the intake and compression of the gasesoccur in the cold portion of the motor, which promote the filling.Furthermore, the volume of the gases admitted in the chamber is about10% greater than the volume of the chamber at the end of the explosion,this can be compared to a natural supercharging.

The gas mixture is first introduced in the chamber of the rotary slidevalve 79 and is then introduced in the motor working chambers throughthe intake openings 80. According to the preferred embodiment, therotary slide valve 79 is constituted by a recessed cylindrical elementcomprising, perpendicularly to its axis of revolution, a terminal wall81 through which it is fixed to a driving shaft 83 rotationally mountedin a bearing and coupled to a gear wheel 84 meshing with a ring gear 85engaged with the rotor 5. The cylindrical wall of the rotary slide valvecomprises a longitudinal opening 82 demarcated by two longitudinaledges.

In the embodiment shown in FIGS. 61 and 63, the angular speed of therotary slide valve 79 is double that of the rotor 5, and the arc ofcircumference of the circle separating the two longitudinal edges of theopening 82 has a value of 180°.

Preferably, the introduction of gas in the chamber of the rotary slidevalve is carried out axially, and the gases are in introduced in theintake chamber by first allowing it to pass through the recessed rotaryslide valve and then through the intake openings.

Advantageously, the rotary slide valve is associated with a lubricatingelement 86 housed in a cylindrical chamber contiguous to that of therotary slide valve 79 and in communication therewith. This lubricatingelement made of a porous and spongy material such as felt is suppliedwith lubricating oil and is subject to come against the externalcylindrical surface of the rotary slide valve 79.

Thus, the rotary slide valve conveys the oil delivered to the gasmixture. This arrangement ensure the lubrication of the motorcapsuling(s).

The motor as described comprises a cooling circuit in which a coolingfluid, such as air, is pulsed.

According to the preferred embodiment, the rotor 8 is recessed and itsaxial perforation constitutes a part of the air cooling circuit. In FIG.62 or 63, one can see that the motor also comprises a water coolingcircuit 95 including a water inlet 96 and outlet 97.

In the body mass of each pair of pistons 10, at least one channel 42 isdug which leads to the axial perforation of the rotor, on the one hand,and to one of the two working chambers not used for the evolution of thegas mixture, on the other hand, this perforation and this capsulingconstitute the other part of the cooling circuit. The cooling fluid isevacuated from this working chamber through the exhaust. The channel 42can be replaced by at least one radial perforation provided in the wallof the rotor 8. Furthermore, a plurality of channels communicating withthe radial bore of the rotor will be provided in the core 13A of thenon-return mechanism. In this way, the non-return mechanism is alsocooled.

Thus, the motor assembly is cooled.

A machine has previously been described which only comprises one motorassembly but includes, in a variation as shown in FIGS. 15-19, and64-66, a plurality of motor assemblies, as many as three, for example,FIGS. 15-19, arranged in a same engine unit, about a common drivingshaft 43 partially arranged in a sealed chamber 44 of the engine unitand rotationally mounted in bearings which are fixedly positioned in thesealed chamber. This driving shaft, exterior to the sealed chamber,receives a gear wheel 45 meshing with ring gears 46 wedged on the rotors5 of the motor assemblies.

The wheels and the gear are sized such that the driving shaft 43 rotatestwice faster than each rotor 5.

According to this embodiment, each motor assembly comprises a hydraulicpump 24 with radial pistons actuated by a rotor, formed on the drivingshaft 43, the rotor being common to all pumps 24. Each pump includes twopistons 87, 88 each mounted in a cylinder 27 and arranged along a sameplane radial to the shaft 43, each piston being actuated in its cylinderby the rotor of the pump. Each pump feeds the rear chamber of thehydraulic motor 25 of the corresponding motor assembly by means of arotating joint 52, and the front chamber of the same hydraulic motor 25by means of a rotating joint 53.

More specifically, the cylinder 27' of one of the pistons is in relationwith the rear chamber of the hydraulic motor 25 by means of the rotatingjoint 52, the other cylinder 27, being in relation with the frontchamber of the hydraulic motor 25 by means of the rotating joint 53.

The rotor is formed by two eccentrics 47 and 48 having the same diameterand being axially spaced apart and offset angularly with respect to oneanother by a 180-degree angle. The two pistons 87, 88 of each pumpcooperate with these two eccentrics, respectively and, by rotation ofthe eccentrics, one of the pistons is actuated in its cylinder 27' inthe retraction direction, whereas the other is actuated in its cylinderin the expansion direction. As previously mentioned, the volumevariations in the cylinders remain substantially equal in the absolutevalue.

Each piston is recessed, to reduce the quantity of moving masses, inparticular. In the housing formed, the piston receives a compressionsspring taking support against the bottom of the cylinder. Thedisplacement of the piston in the direction of the retraction directiontherefore occurs against the action exerted by the compression spring.This compression spring further maintains the contact between the pistonand the eccentric.

Preferably, the piston, via its rod, comes into support against thecylindrical surface of the eccentric by means of a sliding pad 49, thecontacts surfaces between the sliding pad 49 and the associated pistonrod having the shape of a spherical cap to allow for the misalignment.

Preferably, a rotating valve common to all pumps is provided on therotor, this valve being formed by the two eccentrics 47, 48 which, tothis end, are each equipped with a groove 50 dug in their cylindricalsurface along a fraction of their perimeter. According to thisembodiment, each piston rod and the sliding pad 49, aligned with thepath of the corresponding groove, are bored right through. According tothis embodiment, the sealed chamber 44 is filled with oil. Preferably,the upstream ends of the grooves 50 do not have any angular offset fromone eccentric to the other.

During rotation of the driving shaft, the cylindrical chambers 27' ofthe pistons 87, 88 of each pump, and therefore the front and rearchambers of the corresponding hydraulic motor 25 are brought intocommunication with one another by means of the chamber 44 and of thegrooves 50 when said grooves pass beneath the sliding pad, or arehydraulically isolated from one another when the solid portion of thecylindrical surface of each eccentric 47, 48 comes to block the openingof the sliding pad 49.

The blocking of the opening of the pad 49 occurs during the compressionand exhaust phases, this opening being opposite the groove 50 during theintake and explosion phases.

Preferably, the groove 50 of the eccentric assigned to the mobilizationof the pistons of the pumps associated hydraulically with the frontchamber of the corresponding motor 25 extends along an arc of acircumference of a lesser value than that of the arc of circumferencealong which the other groove extends. Thus, the front chamber of eachmotor 25, or motor chamber, is pressurized and supplied before the rearchamber is blocked at the level of the pad 49.

In FIGS. 64, 65 and 66, a thermal machine is shown which is providedwith only two engine units. According to this embodiment, the radialpistons 87, 88 of the pumps are maintained against the eccentrics 47, 48by elastic rings 89 surrounding the rotor common to the radial pistonpumps and each cooperating with the piston of one of the pumps and thepiston of the other. According to the embodiment shown in these Figures,the recess formed in each piston has a truncated shape.

A stationary plug 90 affixed to the body of the pump penetrates intoeach piston.

This arrangement reduces the size of the ullages or of the total volumeof the compressed oil.

In the embodiment shown in FIGS. 64, 65 and 66, each pump is connectedto the corresponding motor by two coaxial and tubular rotating joints91, 92 mounted in one another. One 91 of the tubular joints is incommunication with the rear chambers of the motor, the other being incommunication with the front chambers.

The two rotating joints, which have different lengths, are both engagedin the same cylindrical housing 93 of the body of the pump, in which isarranged an impervious separating partition 94 which divides the housinginto two compartments 93A, 93B and separates the two rotating joints 91,92, from one another. One of the compartments of the housing is incommunication with one 91 of the joints and with one of the cylinders27' of the pump, on the one hand, while the other compartment is inrelation with the other joint and with the other cylinder, on the otherhand.

The hydraulic pump, in its various embodiments, comprises at least onemotor system constituted by one piston 26 and one cylinder 27 associatedwith the front motor chamber of the hydraulic motor and forming,together with the front chamber, a motor hydraulic circuit, and acontrol system constituted by another piston 26 and another cylinder 27,associated with the rear chamber of the hydraulic motor and forming,together with this rear chamber, a control hydraulic circuit.Advantageously, at least one calibrated means is provided for theautomatic discharging of one of the circuits when the pressure in theother reaches a predetermined setting value. Preferably, one calibratedmeans is provided per hydraulic circuit.

Each calibrated means, as can be seen in FIG. 64, and schematically inFIG. 67, is essentially constituted by a pilot operated valve 99 with acalibrated spring 100, this valve being associated with the pressurizedcircuit by means of its pilot, and comprises a piston 101 which isaxially displaceable in a cylinder 102 under the effect of a hydraulicthrust against the action exerted by an elastic return memberconstituting the calibrating element. Furthermore, the piston comprisesa diametral perforation 103 which, when the piston is pushed back in thecylinder by an action equal to or greater than the calibrating value, ispositioned opposite radial perforations 104 provided in the cylinderwall, one of which is in relation with the hydraulic circuit to bedischarged and the other is in relation with this discharge. Eachhydraulic pump 24 according to the embodiments of FIGS. 16-19, and 64and 66, can include a device for the admission of oil in the associatedor suralimentation hydraulic circuit, when the latter is subjected to avacuum.

Advantageously, this device is constituted by a non-return intake valve98. This valve is in relation with the internal volume of the pump, onthe one hand, and with an opening for supplying the oil, on the otherhand. The oil can be pressurized.

In FIG. 64, one can note that the valve 98 is mounted in a housing forthe plug 90. One can also see that this plug is axially bored rightthrough from the housing of the valve.

Finally, it must be noted that the command and control circuits will beequipped with all necessary safety elements. Thus, one can providepressure relief valves associated with each circuit for discharging themwhen the hydraulic pressure is too substantial.

It is understood that the present invention can receive any arrangementsand variations within the field of the technical equivalents, withoutleaving the scope of the present application.

I claim:
 1. A machine usable as a thermal engine comprising:an engineunit having a cylindrical chamber, said engine unit having a first rotorand a second rotor coaxially mounted in said cylindrical chamber, saidrotors and said chamber forming a working chamber which rotates about alongitudinal axis of said cylindrical chamber, said first rotor iscontinuously rotationally driven, said second rotor is intermittentlyrotationally driven in a same direction as said first rotor; atransmission means for rotationally actuating said second rotor bytransmitting movement between said first rotor and said second rotor,said transmission means comprising: an engaging member having anon-return mechanism, said non-return mechanism comprising a firstelement fixed to said engine unit and a second element in engagementwith said second rotor, said first and second elements cooperative witheach other through an angular blocking during an explosion and intakephase of said engine unit, said angular blocking preventing a reversemovement of said second rotor; a hydraulic pump having a rotor coupledto said first rotor, said hydraulic pump having a stator coupled to saidengine unit; a hydraulic motor coupled to said second rotor andconnected to said hydraulic pump by a hydraulic circuit, said hydrauliccircuit being a closed loop or a hydrostatic transmission; at least onevalve means operatively connected to said engaging member, said valvemeans for partially or totally opening said hydraulic circuit betweensaid hydraulic motor and said hydraulic pump during the explosion andintake phase of said engine unit, said valve means for closing saidhydraulic circuit during a compression and exhaust phase of said engineunit, the partial or total opening of said hydraulic circuit fordisengaging said second rotor from said first rotor, the closing of saidhydraulic circuit for engaging said second rotor with said first rotor.2. The machine of claim 1, wherein one of said first and second elementsof said non-return mechanism is a ratchet wheel comprising at least twodiametrically opposed teeth which define two stop positions of saidsecond rotor, another of said first and second elements comprises twodiametrically opposed radial pins, each of said pins being movablymounted in a bore from a set-back position to an exiting position, eachof said pins engages into a corresponding tooth so as to ensure angularblockage of said second rotor along a direction opposite a direction ofrotation of said first rotor, said pins acting as pistons in respectivebores such that said pins exit from and engage into the respective toothby spring action or by hydraulic pressure.
 3. The machine according toclaim 1, wherein said first element of said non-return mechanism isfixed to said engine unit by a mechanical shock absorbing anddissipating means, said mechanical shock absorbing and dissipating meanscomprising a plurality of shock absorbing elements uniformly distributedin an annular area between said first element and said engine unit, saidplurality of shock absorbing elements being in deformable cells eachdefined by two radial walls extending in said annular area, one of saidradial walls being fixed to said first element, another of said radialwalls being fixed to said engine unit.
 4. The machine according to claim1, wherein said first element and said second element of said non-returnmechanism form at least one cell in which a volume of oil is confinedduring the explosion and intake phase to prevent a reverse rotation ofsaid second element.
 5. The machine according to claim 4, wherein saidfirst element comprises a chamber in which said second element ismounted, said chamber extending coaxial to said first and second rotors,said chamber being defined by front and rear walls perpendicular to anaxis of symmetry of said chamber when spaced apart, said chamber alsobeing defined by a casing wall arranged between said front and rearwalls, said second element of said non-return mechanism having a corecoupled to said second rotor, said second element having two bladesextending radially from said core in a diametrically opposite manner,one of said first and second elements of said non-return mechanismcarrying two diametrically opposed sealing members within said chamber,the other of said first and second elements of said non-return mechanismbeing provided with two diametrically opposed surface sectors withrespect to the axis of rotation of said second element, said twodiametrically opposed surface sectors being positioned in said chamber,said sealing members being pressed against said surface sectors whensaid first and second elements are in an angular position of reverseblocking, a surface within said chamber of said casing wall having twodiametrically opposed surface sectors with respect to said axis ofrotation of said second element, said radial blades being pressedagainst said two diametrically opposed surface sectors of said surfacewhen said first and second elements of said non-return mechanism areangularly blocked with respect to one another, a spacing between saidaxis of rotation and said surface sectors of said surface being greaterthan a spacing between said axis of rotation and said surface sectors ofsaid another element of said first and second elements, said chamberhaving a volume between said first and second elements which is filledwith oil, said blades and said sealing members and said surfaces withinsaid chamber of said first and rear walls and said casing wall formingtwo diametrically opposed impervious cells filled with oil when in theposition of angular blocking of said first and second elements, said oilwithin said impervious cells opposing a reverse movement of said secondelement.
 6. The machine according to claim 5, further comprising a meansfor indexing the angular blocking position of said first and secondelements with respect to each other.
 7. The machine according to claim6, wherein said means for indexing allows a reverse movement of saidsecond element toward a blocking position while controlling such reversemovement.
 8. The machine according to claim 7, wherein said two surfacesectors of said surface inside said chamber are adapted to cooperatewith said blades.
 9. The machine according to claim 5, wherein saidblades are slidably mounted in a housing of said core of said secondelement, said sealing members being borne by said core, said sealingmembers being spaced angularly from said blades, said surface sectors ofsaid another element of said first and second elements are formed in aninner surface of said casing wall with an angular spacing from saidsurface sectors of said another element, said surface sectors of saidanother element being adapted to cooperate with said sealing members.10. The machine according to claim 5, wherein said surface sectors ofsaid another element being provided on said core of said second element,said blades of said second element being fixed with respect to saidcore, said sealing members being jouralled to said first element so asto be piloted in their rocking movement toward said core of said secondelement or away therefrom by at least one cam.
 11. The machine accordingto claim 10, said cam being coupled to one of said piston and saidsecond element of said non-return mechanism.
 12. The machine accordingto claim 1, wherein said hydraulic motor is coupled to said first rotorby a stator, said hydraulic motor being coupled to said second rotor bya rotor, said hydraulic pump transmitting oil to said hydraulic motor soas to cause a relative rotation of said second rotor with respect tosaid first rotor.
 13. The machine according to claim 1, wherein saidhydraulic motor comprises one front chamber and one rear chamberconnected to said hydraulic pump by said hydraulic circuit, said valvemeans being a rotating valve which is capable of creating a hydraulicshunt during the intake and explosion phase, said valve means creatingsaid hydraulic shunt by connecting said front and rear chambers of saidhydraulic motor to one another.
 14. The machine according to claim 13,wherein said pump comprises at least two pistons each movable in anindependent chamber, one of said pistons being hydraulically connectedto said front chamber of said hydraulic motor, the other of said twopistons being hydraulically connected to said rear chamber of saidhydraulic motor, a movement of each of said two pistons being oppositeto each other such that the absolute value of instantaneous volumevariations in said chambers is substantially equal.
 15. The machineaccording to claim 13, wherein said hydraulic motor has a first rotorand a second rotor mounted in an interpenetration configuration, saidfirst and second rotors of said hydraulic motor being coupledrespectively to said first and second rotors of said engine unit, saidfirst rotor of said hydraulic motor comprising two diametrically opposedpistons, said second rotor of said hydraulic motor comprisingdiametrically opposed pistons, said hydraulic motor comprising fourworking chambers which are diametrically opposed to each other in atwo-by-two arrangement, two of said working chambers having an interiorvolume which constitutes said rear chamber of said hydraulic motor, theother two working chambers having an internal volume which forms saidfront chamber, said front chamber of said hydraulic motors defined byfaces of said pistons of said rotor of said hydraulic motor and by saidpistons of the other rotor of said hydraulic motor, each piston of saidrotor of said hydraulic motor having conduits opening on both sidesthereof, one of said conduits being a supply conduit and another of saidconduits being a delivery conduit.
 16. The machine according to claim 1,wherein said hydraulic pump has radial pistons, said hydraulic pumphaving a stator which forms a sealed housing in which is mounted arotor, said rotor comprising chambers on said radial pistons whichcooperate with cam surfaces affixed to said stator.
 17. The machineaccording to claim 16, wherein each of said pistons of said hydraulicpump comprises a sliding pad adapted to slide on said cam surfacesprovided in an internal crown of said stator of said hydraulic pump,said sliding pad having a spherical cap-shaped convex surface which issupported in a substantially conical flaring provided in said piston ofsaid hydraulic pump, said sliding pad being provided with two parallelflanks positioned on both sides of said crown, said sliding padcomprises two parallel support lips which are spaced from one another,each of said support lips extending continuously from one flank of saidtwo parallel flanks to the other of said two parallel flanks, said twoparallel support lips having a depression crossing said sliding pad soas to open in the spherical cap-shaped surface of said sliding pad, saidpiston of said hydraulic pump, being crossed by a channel which opens insaid chamber of said piston of said hydraulic pump and in said flaring.18. The machine according to claim 16, said hydraulic motor being formedin said rotor of said hydraulic pump.
 19. The machine according to claim1, said at least one valve comprising a plurality of valves, each of thevalves being controlled in a direction of the opening and closing by therotation of hydraulic jacks, each valve having an axle with adiametrical perforation mounted rotationally in a cylindrical housingprovided in said engine unit and transverse to a radial passage providedin a wall of said engine unit, said radial passage being either anintake or exhaust passage.
 20. The machine according to claim 1, said atleast one valve comprising a plurality of valves, one of said pluralityof valves being a rotary slide valve housed in a cylindrical chamber ofsaid engine unit, said rotary slide valve being contiguous to saidcylindrical chamber, said engine unit having communication openingswhich are alternately blocked and cleared by said rotary slide valveduring an operation of said engine unit.
 21. The machine according toclaim 20, wherein said rotary slide valve has a recessed cylindricalelement having a terminal wall perpendicular to an axis of revolution ofsaid slide valve, said rotary slide valve being fixed to a driving shaftthrough said terminal wall, said rotary slide valve being rotationallymounted in a bearing and coupled to a gear wheel meshing with a ringgear engaged with said first rotor, said cylindrical wall of said rotaryslide valve having a longitudinal opening defined by two longitudinaledges.
 22. The machine according to claim 20, further comprising alubricating element operatively connected to said rotary slide valve andhoused in a cylindrical chamber contiguous with said rotary slide valveand in communication therewith, said lubricating element being of aspongy material supplied with lubricating oil so as to contact a surfaceof said rotary slide valve.
 23. The machine according to claim 1,further comprising:a cooling circuit provided by an axial perforation ina shaft of said second rotor, said cooling circuit having at least onechannel extending to said axial perforation and to said working chamber.24. The machine according to claim 1, further comprising at least twodiametrically opposed working chambers for receiving a gas mixture inaccordance with successive phases of a thermodynamic cycle.
 25. Themachine according to claim 24, wherein two identical phases of thethermodynamic cycle are carried out in two diametrically opposed workingchambers.
 26. The machine according to claim 24, wherein thethermodynamic cycle which occurs in one of said working chambers isoffset in phase with respect to a thermodynamic cycle occurring inanother working chamber.
 27. The machine according to claim 24, whereinsaid two diametrically opposed working chambers are axially offset andseparated from one another by an impervious partition, a gas expansionphase in one of said working chambers corresponds to a gas intake phasein the other of said working chambers.
 28. The machine according toclaim 1, further comprising:a plurality of motor assemblies arranged insaid engine unit about a common driving shaft receiving a gear wheelmeshing with ring gears wedges on said first rotor of said plurality ofmotor assemblies.
 29. The machine according to claim 28, wherein saiddriving shaft is adapted to rotate twice as fast as said first rotor ofeach of said plurality of motor assemblies.
 30. The machine according toclaim 29, wherein each of said plurality of motor assemblies comprises ahydraulic pump with radial pistons actuated by a rotor formed on saiddriving shaft.
 31. The machine according to claim 30, wherein saidhydraulic pump comprises pistons which are each mounted in a cylinderand arranged along a common plane radial to said shaft, each of saidradial pistons being actuated in there respective cylinders by saidrotor of said hydraulic pump, said rotor of said hydraulic pump beingformed by two eccentrics having a similar diameter and axially spacedapart and offset angularly with respect to one another by a 180° angle.32. The machine according to claim 31, wherein said chamber of one ofsaid radial pistons of said hydraulic pump is connected with a rearchamber of a corresponding hydraulic motor by a rotating joint, anothercylinder of another of said radial pistons being connected with a frontchamber of said hydraulic motor by a rotating joint.
 33. The machineaccording to claim 32, said rotating joints of each of the cylindersbeing coaxially mounted in one another, said rotating joints havingdifferent lengths, said rotating joints being engaged in a commoncylindrical housing of said hydraulic pump, said cylindrical housing ofsaid hydraulic pump having an impervious separating partition dividingthe housing into two compartments so as to separate said rotating jointsfrom one another.